Space Shuttle Endeavour launch delayed

UPDATE 1:12 p.m.: a NASA spokesperson says the shuttle delay is now a minimum 72 hours. To access the aft portion of the shuttle and examine the APU (auxiliary power unit) heaters that are malfunctioning, they have to drain the external fuel tank of it's contents - no simple task. That's 500,000 gallons of liquid hydrogen and oxygen.

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Then they'll set up platforms to access that portion of the vehicle, enter the bay and determine if it's a wiring short of if they can simply replace the unit.

That means, as I look at the list of possible launch windows, Monday at 2:33 p.m. would likely be the first time Endeavour can take off.

Rep. Gabby Giffords' spokesperson says "Bummed about the scrub!! But important to make sure everything on shuttle is working properly".

UPDATE 12:28 p.m.: The shuttle launch was scrubbed just three hours before takeoff. There are problems with two heaters on the Auxiliary Power Units. Engineers grew concerned and canceled today's takeoff just as astronauts were riding out to the launch pad. There will be at least a 48 hours turnaround.

2:59 p.m. Sunday is the earliest we believe they could attempt another launch.

NASA will hold a press briefing this afternoon to explain.

Stay tuned for more updates.

UPDATE 11:35 a.m.: Crew members are suiting up in preparation for this afternoon's launch. As of now, everything is still on schedule despite strong cross winds.

(Photo: Astronaut Mike Fincke)

(Photo: Astronaut Mike Fincke)

Actor Seth Green is leading a group of twitter fanatics here at the viewing site for NASA's Twitterup. A small group of manatees are swimming through the basin. Countless cameras are now lining the shore.

UPDATE 10:04 a.m.: All fingers crossed! With the clouds seen in a picture from my previous update still looming, it seems everyone is just hoping for good weather.

I just spoke with an officer from the Air Force Range Weather Operations Facility at Cape Canaveral who says he expects/thinks the storm cell causing concern should be out of the area in about an hour.

As of this minute however, it'd be "red flag" he says ... no launch. We need the low cloud ceiling to move south and rain to stay away. If that happens, we should be good to go.

Also, there was a worry about pressure issues with the OMS, Orbital Maneuvering System, but those have since been worked out. The fuel tanks are now safely loaded/balanced with 500,000 lbs of liquid oxygen and hydrogen. The final inspection team, known as ICE, is also at the pad to do last minute checks.

Now to the fun stuff! Several of the astronauts got up and went for a three mile run today. See a picture below, and if you've ever wondered what you eat for breakfast before heading into space ... keep clicking through the photos: http://yfrog.com/h0tmqulj

UPDATE8 a.m.: NASA is keeping a close eye on these ominous skies. Meanwhile, tanking of the 500,000 lbs of fuel is going as planned. Still a "go" for the 3:47 p.m. launch.

(Photo: Scott Thuman/ABC7)

CAPE CANAVERAL, Fla. (AP) - Six astronauts have said their goodbyes to their families and are ready to take space shuttle Endeavour on its final flight Friday as hundreds of thousands gather along Florida's Space Coast to cheer the spectacle.

Liftoff was set for almost 10 hours after another spectacle was beginning in Britain - the wedding of Prince William and Kate Middleton. The shuttle's huge fuel tank was scheduled for a fill-up at about the same hour they were to exchange vows.

Endeavour weathered a strong thunderstorm Thursday night that dropped hail on a neighboring town and delayed late launch preparations. But that was not expected to interfere with the Friday launch set for 3:47 p.m. Meteorologists predicted a 70 percent chance of good enough weather at liftoff.

Teams at NASA Kennedy Space Center’s Launch Pad 39A now expect to begin moving the rotating service structure away from space shuttle Endeavour at 11:45 p.m. EDT, which still would support a launch attempt tomorrow at 3:47 p.m. EDT. Preparations to move the RSS will begin immediately following the end of the Phase II lightning warning, which is expect to be lifted at approximately 10:15 p.m.

Preliminary data indicates no lightning strikes within half a mile of the pad and no obvious damage to the pad or spacecraft.

VIPs watching Endeavour include President Barack Obama and his family - only the third time a president has witnessed a space launch and the first time a first family has attended one - and so many members of Congress that it's practically a quorum.

But the unseen star is one member of Congress: Arizona Rep. Gabrielle Giffords, the wife of Endeavour's commander, Mark Kelly. Giffords was shot in the head three months ago in an assassination attempt in her hometown of Tucson. A 22-year-old suspect is in custody. Giffords' condition has improved enough that she was able to leave her Houston rehabilitation center to attend her husband's launch - the fourth time she's traveled to Kennedy Space Center to watch a shuttle flight.

The large crowds are expected to start hitting the roads soon after the fuel fills into Endeavour's tank. Officials expect between 500,000 and 750,000 people to crowd around the coastal communities. Delays of several hours are expected on the roads.

This is the last flight of Endeavour and the next to last flight for the 30-year-old space shuttle fleet, after more than 530 million miles of circling the Earth. NASA started the long retirement process for the shuttle fleet in 2004 as part of cost-cutting in order to spend money on new space missions and ships.

Endeavour's launch has one thing William and Kate don't have: a $2 billion international science project. Somewhat overlooked amid the attention on Giffords and Kelly and the president's visit is Endeavour's main mission: It will place a 15,000-pound particle physics detector on the International Space Station. The experiment, which will look for elusive antimatter and the origins of mysterious dark matter, could change man's understanding of the cosmos.

UPDATE Thus., April 28: At 7 p.m. Thursday, severe storms with plenty of lightning and rain were moving across the horizon visible from the launch site. They were close enough that lightning strikes seem to fill the sky over the press center and shuttle assembly building (see photo).

Clouds are seen over Nasa's launch pad Thursday
(Photo: Scott Thuman)

An afternoon brush fire that broke out at the Kennedy Space Center was not considered a major threat to the launch…but was growing a bit in the ‘concern’ department Thursday afternoon. It’s big enough and close enough to the press site that smoke sometimes lofts above the satellite trucks and very slightly obscures the view of the Endeavour.

Word from NASA is the fire is contained, but firefighters have to hope the wind pushes it away from the launch pad (currently it sits three miles away) or there could be issues. The firefighters are not allowed to be in that area tomorrow morning due to its proximity to the pad.

The Endeavour looks majestic sitting on launch pad 39A. It seems anxious to head to the International Space Station and log millions more miles during its 14 days in space, and its final voyage before making its way to a museum in California.

Astronaut Stanley Love with ABC7 reporter
Scott Thuman. (Photo: ABC7)

Astronaut Stanley Love told ABC7’s Scptt Thuman it’s sad to see the program go. There’s an uncertain future for some 7,000 NASA employees, maybe more. Love acknowledged though that the trips to space are more costly than predicted, and sadly, more dangerous.

As for all of the attention, he wondered aloud where everyone has been over the past two decades, noting it’s a shame more people are watching now, because only two launches remain.

Giffords' whereabouts, meanwhile, were being kept secret. She is married to Endeavour's commander, Mark Kelly, who will lead a six-man crew to the International Space Station. They're delivering spare parts and a $2 billion particle physics experiment aboard the shuttle.

A staff member for Giffords said in a Twitter update Thursday that she was enjoying Florida and "all the space action." She arrived in Cape Canaveral on Wednesday, leaving behind the Houston hospital where she has been undergoing rehab for three months.

NASA officials said they did not know where Giffords would view the launch. Obama and his wife, Michelle, and two daughters were to watch with NASA chief Charles Bolden Jr. from an area near launch controllers.